NRC to supplement Yucca Mountain environmental impact statement

13 March 2015

The US Nuclear Regulatory Commission (NRC) will prepare a supplement to the Department of Energy's environmental impact statement (EIS) on the proposed geologic repository for spent nuclear fuel and high-level radioactive waste at Yucca Mountain in Nevada. The public were informed yesterday via a notice in the Federal Register.

The commission found that the EIS the Department of Energy (DOE) submitted in 2008 did not adequately address all of the repository-related effects on groundwater, or from surface discharges of groundwater. In 2013, it asked DOE to prepare a supplement. Instead, DOE updated its analysis of potential groundwater impacts after closure of a repository at the site, and in February 2015 the NRC directed its staff to prepare the supplement. They will use the DOE analysis in preparing the supplement.

The supplement will describe a key aquifer at the site and look at the potential for contaminants to reach it. It will analyze the degree of potential contamination and how water and contaminants could move. And it will discuss how soil, surface materials and the surrounding environment might be impacted by contaminated groundwater.

The NRC expects to issue a draft supplement for public comment in late summer. During the comment period, the NRC plans to hold three public meetings – two in Nevada and one at its headquarters in Rockville, Maryland – and a public webcast and teleconference.

The NRC expects to issue a final supplement next spring.

In January, the NRC published the final two volumes of its safety evaluation report for the proposed Yucca Mountain geologic nuclear waste repository, completing the technical safety review of DOE's application. The final volumes to be published are volume 2, covering repository safety before permanent closure, and volume 5, which covers proposed conditions on the construction authorisation, likely licence specifications and overall conclusions. All five volumes of the report are now available on the NRC's website.

The US government is legally responsible for developing a long-term disposal strategy for used nuclear fuel. From 1992 until 2009, that strategy had been Yucca Mountain. The DOE announced a new waste disposal strategy in early 2013, envisaging a series of interim stores until a permanent underground disposal facility is ready for service around 2048.